The concept of freezing ice in the winter and using it to provide cooling in the summer is old, particularly for food refrigeration wherein blocks of naturally frozen water were sawn and stored in an ice house to be used in the summer for food preservation. With the advent of mechanical refrigeration cycles and the widespread availability of electrical power, stored ice declined in utilization. However, in the new energy concious age, the concept of long-term thermal energy storage is becoming more popular as increased utilization of solar energy is considered due to the energy crisis.
One example of such a system is the use of a large tank of water to store the summer heat for use in providing winter heat. Another example is the ACES (Annual Cycle Energy System) system in which ice is produced during the winter utilizing the waste heat from a heat pump that is heating the residence. The stored ice is then used for summer cooling. The ACES system is described in a report, "Design Report for the ACES Demonstration House," Oak Ridge National Laboratory, ORNL/COM-1 (October 1976) by A. C. Hise et al. Both of these systems are active systems which require pumps, valves and sensors to be operating while energy is being stored.
It is therefore an object of this invention to provide a system of storing the cold of the winter for utilization as a source of cooling.
Another object of this invention is to provide a passive system for storing a source of cooling.